diff --git a/README.md b/README.md index 4278241..dbc5803 100644 --- a/README.md +++ b/README.md @@ -20,7 +20,7 @@ For simplicity, many of the code examples here operate on floating point values - [variable name conventions](#variable-name-conventions) - [equals `=` `≈` `≠` `=:`](#equals-symbols) -- [dot & cross `·` `×`](#dot--cross) +- [dot & cross `∙` `×` `∘`](#dot--cross) - [scalar multiplication](#scalar-multiplication) - [vector multiplication](#vector-multiplication) - [dot product](#dot-product) @@ -104,7 +104,7 @@ The `≅` symbol is for [*congruence*](https://en.wikipedia.org/wiki/Congruence_ ## dot & cross -The dot `·` and cross `×` symbols have different uses depending on context. +The dot `∙` and cross `×` symbols have different uses depending on context. They might seem obvious, but it's important to understand the subtle differences before we continue into other sections. @@ -132,13 +132,13 @@ var result = 3 * k * j #### vector multiplication -To denote multiplication of one vector by another, or multiplication of a vector with a scalar, we do not use the dot `·` or cross `×` symbols. These have different meanings in linear algebra, discussed shortly. +To denote multiplication of one vector with a scalar, or element-wise multiplication of a vector with another vector, we do not use the dot `∙` or cross `×` symbols. These have different meanings in linear algebra, discussed shortly. -Let's take our earlier example but apply it to vectors: +Let's take our earlier example but apply it to vectors. For element-wise vector multiplication, you might often see an open dot `∘` to represent the [Hadamard product](https://en.wikipedia.org/wiki/Hadamard_product_%28matrices%29). ![dotcross3](img/dotcross3.png) - + Here is how it would look in code, using arrays `[x, y]` to represent the 2D vectors. @@ -164,11 +164,11 @@ function multiplyScalar(a, scalar) { } ``` -Similarly, matrix multiplication typically does not use a dot or cross symbol. Matrix multiplication will be covered in a later section. +Similarly, matrix multiplication typically does not use the dot `∙` or cross symbol `×`. Matrix multiplication will be covered in a later section. #### dot product -The dot symbol `·` can be used to denote the [*dot product*](https://en.wikipedia.org/wiki/Dot_product) of two vectors. Sometimes this is called the *scalar product* since it evaluates to a scalar. +The dot symbol `∙` can be used to denote the [*dot product*](https://en.wikipedia.org/wiki/Dot_product) of two vectors. Sometimes this is called the *scalar product* since it evaluates to a scalar. ![dotcross4](img/dotcross4.png) diff --git a/img/dotcross3.png b/img/dotcross3.png index 6e9bba7..eeff2ca 100644 Binary files a/img/dotcross3.png and b/img/dotcross3.png differ